Piston for rotary steam motors



Nov. 26, 1929. R. J. BOGUE 1,737,355

PISTON FOR ROTARY STEAM MOTORS Filed June 1926 2 Sheets-Sheet 1 Nov. 26, 1929. R. J. BOGUE PISTON FOR ROTARY STEAM MOTORS ZSheets-Sheet 2 Filed June 5, 1926 ammm (7: 0 awe Patented Nov. 26, 1929 earear errrcs Bonnier J. 'BOGUE, or eoon nrerrr, TEXAS risron non ROTARY STEAM Morons Application filed June 3,

This invention supplies a piston for a rotary steam motor of novel and peculiar construction embodying packing which is forced outwardly by steam pressure to main- '5 tain a close joint with the chambers to prevent loss of pressure.

.While the drawings illustrate a preferred embodiment of the invention, it is to be understood that in adapting the means to meet specific needs and requirements, the design may be varied and changes in the minor details o'f-construction maybe resorted to within the scope of the invention as claimed, without I departing from the spirit thereof;

For a full understanding of the invention andthe merits thereof, reference is to be had to the following description and the drawings hereto attached, in which,-

Figure 1 is a side view of a rotary engine embodying the invention,

' Figure 2' is a'vertical transverse sectional view on the line 2-2 of Figure 1,

Figure 3 is anenlarged viewof one of the pistonsuthe near plate'being-omitted,

Figure dis a longitudinal edge view of a piston,

Figure 5 is a detail sectional view on line 55 of Figure 4, and I Figure 6 is a detail perspective view-of the exp ansible packingo'f one of the pistons (an d the strips .coacting therewith @to maintain a tight-joint between theoverlapping ends of adj acent elements.

Corresponding and like :parts are referred :to in the "following description and desigmated .111 the several views :of the drawings by Elike meference characters.

The stator comprises similar sides 1 and .2 which are bolted or otherwise secured tolgetherto form a statoror casing for reception of the rotor 18 which'obtains a snug fit therein, there being packing 3 between the meeting faces to ,preserve a steam tight ,joint. The .rotor 18 is keyed or otherwisesmade fast to a .shaft i which is mounted centrally of the side members, the projecting ends of the shaft 4 receiving pulleys or fly wheels 5. Each of the side members comprising the stator 'is provided with concentric chambers in whi'chthe ends of the pistons carried by the 1926. Serial No. 113,576.

The steam or like ex ansive motive medium G5 is supplied to one end of the chamber 6 by means of a pipe '8 connected with a suitable sourceof supply, and the opposite end of the chamber *6 communicates with one end 'ofthechamber 7 sot-hat'the spent steam from a the chambert enters "the chamber 7 and operates therein by expansion. The outlet at the opposite end of the chamber 7 opens into the atmosphere for discharge of the steam after it has operated expansively. The side member 2 is provided with an innercircumferential'chamber.12 corresponding to the circumferential chamber 6 of the side member 1. The chamber 12 has a reverse arrangement to the chamber 6, that is, the space formed between the ends thereof is located directly opposite the middle portion ofthe chamber 6. This brings the space 2 between the ends of the chamber 6 directly opposite the middle portion of the chamber .12. 'The'side member2 is also provided with a circumferential chamber 13 corresponding to the chamber 7 and having .a reverse ar :rangement, that "is, with the space between its ends arranged diametrically opposite the space midway between'the endsofthe cham- *ber v7. @pposite ends of the several chambers are 'reversely inclined and the intermediate portion is of a uniform depth, A pipe 1 1- leading from a suitable source of' steam supply communicates with the inlet at one end of the chamber 12. The outlet at the opposite end of the chamber 12 communicates with one end of the chamber 13 L and provides for discharge of the steam from the chamber 12 into the chamber 13 to operate therein by expansive action. The outlet at the opposite end of the chamber 13 provides for discharge of the steam therefrom into the open air.

The rotor 18 is; provided at diametrically opposite points with'a pair of transverse openings in line with the respective inner and outer concentric chambersw Pistons 21 are mounted in the openings alined with the chambers 6 and 12 to slide transversely o f' t'he rotor and alternately operate in said chambers. Other pistons 22 are similarly mounted in the openings alined with the chambers 7 and 13. The pistons 21 and 22 are of like construction, the only difference residing in the width, the pistons 22 being wider than the pistons 21 to correspond with the width of the outer chambers 7 and 13; At one position of the rotor 18, as shown most clearly in Figure 2 of the drawings, the end portion of one of the pistons 21 projects into the chamber 12 and the opposite end of the piston is in engagement with the side of the stator in the space between the ends of the chamber 6. The other piston 21 at the same time has its opposite end portion projected into the chamber .6 and its other end in the space formed between the ends of the chamher 12. The outerpistons 22 are reversely disposed,the end of one piston projecting into the chamber 7 and the opposite end of the other piston projecting into the chamber 13. Roller bearings are provided upon the sides of the rotor at sides of the respective pistons 21 and 22 so as to minimize the resistance to their transverse sliding movements.

The pistons areof like formation, the construction being shown in detail in Figures 3 to 6, both inclusive. Each of the pistons comprises a middle plate 25 and side plates 26, the several plates being of like Width and length. 'The side plates 26 are of uniform thickness throughout whereas the middle plate25 has its central portion 27 of greater thickness than its marginal portions and projecting upon opposite sides to a like extent,

. whereby to provide marginal spaces between the several plates for the reception of packing to maintain a steam tight joint between .the pistons and the, walls of the chambers and the openings in which the pistons are mounted. The raised portion 27 at each side of the middle plat-e 25is formed at each end with a transverse channel 28 and a lon ituditransversechannel 28 to supply steam there-- wardly'to main a steam tight joint.

packing at each side of the middle plate 25 05 nal channel 29 in communication at its inner end with the transverse channel 28. Openings 30 are formed in end portions of the side plates 26 and communicate with the to, which is utilized to force the packing out- The consists of four an le elements 31 havin channels 28 and 29 and passes into the spaces 32, thereby forcing the strips 33 and the packing elements outwardly, with the result that loss of pressure is prevented and a steam tight joint between the pistons and the walls of the chambers and the openings of the rotor is maintained.

In the operation of the engine live steam' at boiler pressure is admitted to each of the inner chambers 6 and 12 by means ofthe pipes 8 and 14. This steam operates upont-he end portions of the pistons 21 projecting into'the respective chambers 6 and 12, thereby imparting a rotary movement to the rotor 18.

When the rotor reaches a point in its travel to.

uncover the respective outlet ports the live steam passes from the respectivechambers 6 and 12 into the outer expansion chambers77 and 13 and operates expansively on the respective pistons 22, the end portions of which project into the respective expansion chambers. The'motor now continues to oper'ate both by direct pressure of the steam and by expansive action thereof and the respective pistons 21 and 22 are alternately shifted from one chamber to the other, as will be readily appreciated. The steam after acting expansively escapes into the atmosphere. The in-' ner sides of the several chambers are closed by the rotor and the packing 3 is disposed to maintain a steam tight joint at the outer walls of the chambers. As shown most clearly in Figure 2 of the drawings, opposite ends of corresponding pistons project beyond oppo-' sitesides of the rotor, hence the drivin'g'force of the steam is expended uniformly upon opposite sides of the rotor, thereby preventing any binding or torsional action. The bottom walls of the respective. chambers incline at oppositeends thereof to insure a shifting of the pistons, as they reach the ends of the respective chambers and the, construction is such as to provide chambers of "practically uniform depth, the end portions of corresponding" chambers being opposite one another and reversely inclined, as shown most clearly in Figure 6. The inner chambers 6 and12 are of less capacity than the outer chambers 7 and 13 and this is of advantage in the conservation of power and the utilization thereof to the best possible advantage because the expanding steam acts upon a greater ton area than the live steam at boiler pres sure.

Having thus described the invention, I claim:

' 5 1. A piston comprising a rectangular plate having a raised central portion formed in its outer side with intersecting transverse and longitudinal channels, a companion plate coextensive with the first mentioned plate and 10 placed against the raised portion thereof, and 7 having openings in communication with the said channels, packing in the space f0r med between the marginal portions of the two plates exterior to the said raised portion and 15 having the meeting ends halved and overlapped, and strips in the marginal space in the rear of the packing to close the joints between the meeting ends thereof.

2. A piston comprising rectangular and co- 2 extensive middle and side plates, the middle plate having a centrally disposed raised portion at each side forming spaces between the marginal portions of the plates, the raised portions of the middle plate having intersecting transverse and longitudinal channels in their outer sides, and the side plates having openings in connection with the intersecting channels, angle packing in the marginal spaces having the meeting ends halved 33 and overlapped, and strips in the spaces in the rear of the packing and closing the joints between the meeting ends thereof.

In testimony whereof I afix my signature.

ROBERT J. BOGUE. [ns] 

